Divergent synthesis of CF3-substituted polycyclic skeletons based on control of activation site of acid catalysts

2018 ◽  
Vol 54 (50) ◽  
pp. 6927-6930 ◽  
Author(s):  
Kazuma Yokoo ◽  
Keiji Mori
Keyword(s):  
Acid Catalysts ◽  
Precise Control ◽  
Selection Of ◽  
Activation Site

We report a divergent synthesis of CF3-substituted fused skeletons based on precise control of the activation site through the selection of acid catalysts.

Servo respirator constructed from a positive-pressure ventilator

1976 ◽  
Vol 41 (2) ◽  
pp. 252-255 ◽  
Author(s):  
J. E. Remmers ◽  
H. Gautier
Keyword(s):  
Negative Feedback ◽  
Differential Amplifier ◽  
Positive Pressure ◽  
Precise Control ◽  
Pressure Signal ◽  
Response Characteristics ◽  
Tracheal Pressure ◽  
Selection Of

We have constructed an electronically controlled respirator from three commercially available components: a positive-pressure ventilator, a recorder pen motor, and a differential amplifier. Using negative feedback derived from a tracheal pressure signal, the instrument functions as a servo respirator which provides precise control of tracheal pressure. The system's power and response characteristics are well suited for ventilation of anesthetized cats and dogs. The servo respirator can be used as an externallycontrolled respiratory pump which provides flexibility in selection of the parameters of the ventilatory cycle. Alternatively, it can function as a “demand” respirator which generates transthoracic pressure proportional to efferent respiratory discharge.

scholarly journals Are trade-offs between flexibility and efficiency in systematic conservation planning avoidable ?

2019 ◽  
Author(s):  
Sabrine Drira ◽  
Frida Ben Rais Lasram ◽  
Tarek Hattab ◽  
Yunne Jai Shin ◽  
Amel Ben Rejeb Jenhani ◽  
...  
Keyword(s):  
Conservation Planning ◽  
Large Body ◽  
Efficient Solutions ◽  
Reserve Selection ◽  
Systematic Conservation Planning ◽  
Distribution Models ◽  
Precise Control ◽  
Trade Offs ◽  
Selection Framework ◽  
Selection Of

AbstractSpecies distribution models (SDMs) have been proposed as a way to provide robust inference about species-specific sites suitabilities, and have been increasingly used in systematic conservation planning (SCP) applications. However, despite the fact that the use of SDMs in SCP may raise some potential issues, conservation studies have overlooked to assess the implications of SDMs uncertainties. The integration of these uncertainties in conservation solutions requires the development of a reserve-selection approach based on a suitable optimization algorithm. A large body of research has shown that exact optimization algorithms give very precise control over the gap to optimality of conservation solutions. However, their major shortcoming is that they generate a single binary and indivisible solution. Therefore, they provide no flexibility in the implementation of conservation solutions by stakeholders. On the other hand, heuristic decision-support systems provide large amounts of sub-optimal solutions, and therefore more flexibility. This flexibility arises from the availability of many alternative and sub-optimal conservation solutions. The two principles of efficiency and flexibility are implicitly linked in conservation applications, with the most mathematically efficient solutions being inflexible and the flexible solutions provided by heuristics suffering sub-optimality. In order to avoid the trade-offs between flexibility and efficiency in systematic conservation planning, we propose in this paper a new reserve-selection framework based on mathematical programming optimization combined with a post-selection of SDM outputs. This approach leads to a reserve-selection framework that might provide flexibility while simultaneously addressing efficiency and representativeness of conservation solutions and the adequacy of conservation targets. To exemplify the approach we a nalyzed an experimental design crossing pre- and post-selection of SDM outputs versus heuristics and exact mathematical optimizations. We used the Mediterranean Sea as a biogeographical template for our analyses, integrating the outputs of 8 SDM techniques for 438 fishes species.

Room-Temperature Ceramic Nanocoating Using Nanosheet Deposition Technique

2013 ◽  
Vol 2013 (CICMT) ◽  
pp. 000014-000018 ◽  
Author(s):  
M. Osada ◽  
T. Sasaki
Keyword(s):  
Room Temperature ◽  
Organic Molecules ◽  
Structural Diversity ◽  
Layer By Layer ◽  
Precise Control ◽  
Langmuir Blodgett ◽  
Wide Range ◽  
Potential Applications ◽  
Layer Assembly ◽  
Selection Of

We present a novel procedure for ceramic nanocoating using oxide nanosheet as a building block. A variety of oxide nanosheets (such as Ti1−δO2, MnO2 and perovsites) were synthesized by delaminating appropriate layered precursors into their molecular single sheets. These nanosheets are exceptionally rich in both structural diversity and electronic properties, with potential applications including conductors, semiconductors, insulators, and ferromagnets. Another attractive aspect is that nanosheets can be organized into various nanoarchitectures by applying solution-based synthetic techniques involving electrostatic layer-by-layer assembly and Langmuir-Blodgett deposition. It is even possible to tailor superlattice assemblies, incorporating into the nanosheet galleries with a wide range of materials such as organic molecules, polymers, and inorganic/metal nanoparticles. Sophisticated functionalities or paper-like devices can be designed through the selection of nanosheets and combining materials, and precise control over their arrangement at the molecular scale.

Ability to Control the Glass Transition Temperature of Amorphous Shape-Memory Polyesterurethane Networks by Varying Prepolymers in Molecular Mass as well as in Type and Content of Incorporated Comonomers

2009 ◽  
Vol 1190 ◽  
Author(s):  
Joerg Zotzmann ◽  
Steffen Kelch ◽  
Armin Alteheld ◽  
Marc Behl ◽  
Andreas Lendlein
Keyword(s):  
Glass Transition ◽  
Minimally Invasive Surgery ◽  
Shape Memory ◽  
Molecular Mass ◽  
Amorphous Polymer ◽  
Polymer Networks ◽  
Precise Control ◽  
Low Weight ◽  
Switching Temperature ◽  
Selection Of

AbstractThe need of intelligent implant materials for applications in the area of minimally invasive surgery leads to tremendous attention for polymers which combine degradability and shape-memory capability. Application of heat, and thereby exceeding a certain switching temperature Tsw, causes the device to changes its shape. The precise control of Tsw is particularly challenging. It was investigated in how far Tg, that can be used as Tsw, of amorphous polymer networks from star-shaped polyester macrotetrols crosslinked with a low-weight linker can be controlled systematically by incorporation of different comonomers into poly(rac-lactide) prepolymers. The molecular mass of the prepolymers as well as type and content of the comonomers was varied. The Tg could be adjusted by selection of comonomer type and ratio without affecting the advantageous elastic properties of the polymer networks.

ChemInform Abstract: Chance and Necessity in the Selection of Nucleic Acid Catalysts

ChemInform ◽  
2010 ◽  
Vol 27 (23) ◽  
pp. no-no
Author(s):  
J. R. LORSCH ◽  
J. W. SZOSTAK
Keyword(s):  
Nucleic Acid ◽  
Acid Catalysts ◽  
Selection Of

How to Optimize Critical Current Performance of RE123 Materials by Controlling Oxygen Content

2001 ◽  
Vol 689 ◽  
Author(s):  
Jun-ichi Shimoyama ◽  
Shigeru Horii ◽  
Kenji Otzschi ◽  
Kohji Kishio
Keyword(s):  
Oxygen Partial Pressure ◽  
Partial Pressure ◽  
Critical Current ◽  
Oxygen Content ◽  
Oxygen Nonstoichiometry ◽  
Thermodynamic Quantities ◽  
Precise Control ◽  
Oxygen Defects ◽  
Re Elements ◽  
Selection Of

ABSTRACTOxygen nonstoichiometry behaviors of REBa2Cu3Oy (RE123: RE= Nd, Sm, Eu, Gd, Dy. Ho and Y) compounds have been precisely determined by the thermogravimetric measurements. Dependence of oxygen content on temperature and oxygen partial pressure were found to slightly depend on the RE element. Thermodynamic quantities of oxygen, such as hO2 and sO2, also varied with RE element. Relationship between Tc and oxygen content is strongly dependent on the RE species. This suggests that pinnig effect due to the oxygen defects is different in each RE123 compound and, therefore, critical current properties of RE123 must be optimized by precise control of oxygen content as well as selection of suitable RE elements.

scholarly journals Optimization of crystallization of biological macromolecules using dialysis combined with temperature control

2020 ◽  
Vol 53 (3) ◽  
pp. 686-698 ◽  
Author(s):  
Niels Junius ◽  
Elham Vahdatahar ◽  
Esko Oksanen ◽  
Jean-Luc Ferrer ◽  
Monika Budayova-Spano
Keyword(s):  
Phase Diagram ◽  
Crystal Growth ◽  
Crystal Size ◽  
Physical Parameters ◽  
Biological Macromolecules ◽  
Precise Control ◽  
Starting Position ◽  
Crystallization Experiment ◽  
Metastable Zone ◽  
Selection Of

A rational way to find the appropriate conditions to grow crystal samples for bio-crystallography is to determine the crystallization phase diagram, which allows precise control of the parameters affecting the crystal growth process. First, the nucleation is induced at supersaturated conditions close to the solubility boundary between the nucleation and metastable regions. Then, crystal growth is further achieved in the metastable zone – which is the optimal location for slow and ordered crystal expansion – by modulation of specific physical parameters. Recently, a prototype of an integrated apparatus for the rational optimization of crystal growth by mapping and manipulating temperature–precipitant–concentration phase diagrams has been constructed. Here, it is demonstrated that a thorough knowledge of the phase diagram is vital in any crystallization experiment. The relevance of the selection of the starting position and the kinetic pathway undertaken in controlling most of the final properties of the synthesized crystals is shown. The rational crystallization optimization strategies developed and presented here allow tailoring of crystal size and diffraction quality, significantly reducing the time, effort and amount of expensive protein material required for structure determination.

scholarly journals Implementation of Ring-Oscillators-Based Physical Unclonable Functions with Independent Bits in the Response

2012 ◽  
Vol 2012 ◽  
pp. 1-13 ◽  
Author(s):  
Florent Bernard ◽  
Viktor Fischer ◽  
Crina Costea ◽  
Robert Fouquet
Keyword(s):  
Power Consumption ◽  
Integrated Circuit ◽  
Ring Oscillators ◽  
Physical Unclonable Functions ◽  
Precise Control ◽  
Placement And Routing ◽  
Unique Signature ◽  
Selection Of

The paper analyzes and proposes some enhancements of Ring-Oscillators-based Physical Unclonable Functions (PUFs). PUFs are used to extract a unique signature of an integrated circuit in order to authenticate a device and/or to generate a key. We show that designers of RO PUFs implemented in FPGAs need a precise control of placement and routing and an appropriate selection of ROs pairs to get independent bits in the PUF response. We provide a method to identify which comparisons are suitable when selecting pairs of ROs. Dealing with power consumption, we propose a simple improvement that reduces the consumption of the PUF published by Suh et al. in 2007 by up to 96.6%. Last but not least, we point out that ring oscillators significantly influence one another and can even be locked. This questions the reliability of the PUF and should be taken into account during the design.

Tailored design of CoxMn1−xFe2O4 nanoferrites: a new route for dual control of size and magnetic properties

2014 ◽  
Vol 2 (29) ◽  
pp. 5818-5828 ◽  
Author(s):  
Carlos Fernandes ◽  
Clara Pereira ◽  
María Paz Fernández-García ◽  
André M. Pereira ◽  
Alexandra Guedes ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Material Properties ◽  
Dual Control ◽  
One Pot ◽  
Precise Control ◽  
Alkaline Agent ◽  
Tailored Design ◽  
Selection Of

CoxMn1-xFe2O4 nanoferrites with tailored size and magnetism were produced by one-pot coprecipitation. Selection of Co(II):Mn(II) ratio and alkaline agent allows precise control of the material properties.

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